intestinal obstruction

1. INTESTINAL OBSTRUCTION Supervisor : Dr. Hilda Prepared by: Ahmad Iqbal Syafiq Zuhratun Nazihah

2. Outlines DEFINITION CLASSIFICATION CAUSES HISTORY EXAMINATION INVESTIGATION PSEUDO-OBSTRUCTION MANAGEMENT SURGERY : INDICATIONs TAKE HOME MESSAGES

3. Definition Intestinal obstruction is blockage of bowel that prevents the contents of the intestine from passing through.

4. Classification Paralytic ileus Postoperative Inflammatory Metabolic neurogenic Extramural Intramural Intraluminal

5. Mechanical

6. ELDERLY – carcinoma, diverticulitis, sigmoid volvulus ADULT – hernia, adhesion, carcinoma PAEDIATRICS – intussusception , congenital hypertrophic pyloric stenosis , atresia (duodenum, ileum), meconium obstruction, volvulus neonatorum

7. Pathophysiology

8. Pathophysiology Bowel distal to obstruction collapse Bowel proximal to obstruction distends and becomes hyperactive (distension due to intestinal secretions and swallowed air) Bowel wall becomes edematous. Fluid electrolytes accumulate in the wall and lumen (third space loss) Bacteria proliferate in the obstructed bowel As the bowel distends, intramural vessels become stretched/compromised Ischemia and necrosis

9. History 4 Cardinal Signs : Abdominal pain Nausea & vomiting Abdominal distension Absolute constipation Others : Dehydration, hypotension, tachycardia, pyrexia, abdominal tenderness, empty rectum on DRE, high pitched bowel sound .

10. Pain Small bowel : - periumbilical and colicky - comes in spasm - builds up in crescendo - then tappers off - regular pain at intervals of 2-3 minutes Large bowel : below the umbilicus & comes at intervals of 6-10 minutes. Severe & continuous pain suggest strangulation obstruction.

11. Vomiting The higher the obstruction, the vomiting is more severe In large bowel obstruction vomiting comes later and sometimes patient may not vomit at all. As obstruction progresses the character of the vomitus alters (digested food  feculent material; as a result of the presence of enteric bacterial overgrowth)

12. Abdominal distention The more distal the obstruction, the more distention of abdomen. Visible peristalsis may be present. Constipation May pass feces or flatus if early onset Occurs early in lower large bowel obstruction Occurs late in high small bowel obstruction Absolute constipation is a feature of complete intestinal obstruction.

13. In high small bowel obstruction, vomiting occurs early and is profuse with rapid dehydration. Distension is minimal In low small bowel obstruction, Vomiting is delayed. pain is predominant with central distension. In large bowel obstruction, distension is early and pronounced. Pain is mild and vomiting and dehydration are late.

14. Examination Inspection Visible scar -band -adhesion Palpation hernial orifices large, slightly tender, mobile mass changes its position with colicky pain tender indurated mass hard impacted masses -incarcerated -strangulated hernia +torsion +intussusception -mass of Ascaris worms + intraperitoneal abscess - fecaloma

15. Percussion - tympanic sound Auscultation -runs of borborygmi -tinkling high pitched musical sounds Rectal examination fresh blood and mucus hard mass of faeces hard mass in the rectovesical pouch -strangulating lesion -carcinoma of large gut -intussusception +constipation - extraintestinal tumour

16. Investigation Blood FBC : Hb  anaemic PCV  elevated due to dehydration TWBC  normal or elevated (strangulation, ischemia, perforation) RP: dehydration electrolyte imbalance (hypokalemia, hyponatremia) ABG: alkalosis  proximal obstruction (severe vomiting) acidosis  strangulation

17. Radiological AXR Gas pattern Fluid level Masses shadow Fecal pattern Chest X-Ray Elevated diaphragm Air under diaphragm Aspiration

18. USG: to differentiate mechanical obstruction & paralytic ileus, poor visualization of gas filled structure, only useful in selected patient ie pregnant, when CT is contraindicated, in critically ill patients Free fluid Masses Mucosal folds Pattern of peristalsis CT scan: level of obstruction (transition point) Causes (hernias, inflammatory changes, masses) sign of strangulation, ischemia, perforation

19. Large Bowel: Small Bowel: Peripheral Presence of haustration , diameter >8 cm distended caecum  a rounded gas shadow in the right iliac fossa . >10cm diameter. Central jejunum  valvulae conniventes Ileum  featureless Diameter >5 cm No gas is seen in the colon

20. Pseudo-obstruction DEFINITION Describes an obstruction that occurs in the absence of mechanical cause or acute intra abdominal disease Diagnosis of exclusion in the absence of mechanical cause CAUSES Idiopathic Metabolic Severe trauma Shock Septicaemic Retroperitoneal irritation Drugs

21. Ogilvie’s Syndrome Acute large bowel obstruction Absence of mechanical cause AXR – evidence of colonic obstruction, usually marked cecal distension Single contrast water soluble barium enema, CT scan and colonoscopy can be done Once diagnosis confirmed, treat with colonoscopic decompression Recurrence occurs in 25% Complication – cecal perforation Repeat colonoscopy with simultaneous placement of flatus tube may be required Surgical intervention – subtotal colectomy and ileorectal anastomosis

22. Principles of Treatment Gastrointestinal drainage Fluid and electrolytes replacement Relief of obstruction Surgical intervention necessary for most cases Need to be delayed until resuscitation is complete

23. Early Management ABC Resuscitation Oxygen supply fluid replacement with hartman or normal saline Nasogastric decompression KNBM NG tube with free flow or 4hly aspirate Close monitoring BP, PR, Temp, Input/output, CVP Antibiotic s cover Analgesia

24. Indication For Surgery Immediate intervention Evidence of strangulation Signs of peritonitis resulting from perforation or ischemia In the next 24-48H Clear indication of no resolution of obstruction (clinical or radiological) Diagnosis is unclear in virgin abdomen

25. Take Home Message 4 cardinal signs of intestinal obstruction are abdominal pain, abdominal distension, vomiting and constipation Pseudo-obstruction is the diagnosis of exclusion in the absence of mechanical obstruction Decompress the obstructed gut (NGT!!)

26. Replace fluid and electrolytes loses Strict IO (CBD is least, CVP - especially in elderly, immuno compromised patient) CT if only patient is stable and cause of obstruction is unclear Surgical intervention promptly if signs of peritonitis or strangulation, underlying cause needs surgical treatment ie colonic carcinoma or hernias or patient does not improve with conservative treatment

27. References http://www.primary-surgery.org/ps/vol1/ch-10.pdf Bailey & Love’s Short Practice Of Surgery 25 th edition